In modern motor vehicles electronic components are being increasingly installed and used, and these react in sensitive manner to magnetic fields prevailing in their surroundings. Sensors may also be used in various areas, whose operating principle is based on the measuring of magnetic fields, such as is the case with Hall sensors, for example. Especially when starting internal combustion engines by way of a starter or when operating electric motors which propel the motor vehicle, currents flow with great current strength, and they generate strong magnetic fields accordingly. In the prior art, various solutions are proposed on how to attenuate or weaken in general the magnetic fields generated by current-carrying lines.
Thus, the document JP 2003061268 A shows a non-contact transmission system for transmitting electrical energy to a vehicle from a line layout having a forward and a return line. Thanks to special configurations of the current consumer of the vehicle, it becomes possible to arrange the current-carrying feed line and the current-carrying return line at a shorter distance from each other, so that the magnetic field generated by the lines is decreased in their vicinity.
Document EP 2 138 859 A1 shows a heater with current-carrying lines which are laid out and inductively coupled so that the magnetic fields of the individual current-carrying lines propagate in opposite directions and thus mutually diminish each other.
Document DE 296 13 339 U1 discloses an electrically operated heating element in which the power supply is divided among at least two heated current conductors, so that the current conductors can be led in pairs in the heating element. Thanks to this paired layout of the current-carrying current conductors, the magnetic fields built up in the vicinity of the heating element are attenuated.
The solutions described in the prior art have the common feature that at least two current-carrying lines are arranged relative to each other in such a way that the resulting magnetic fields overall are weakened by currents flowing in the opposite direction. Such a solution is not always practical for use in a motor vehicle, because such a solution involves significant expense in the power supply inside the motor vehicle.